• 기술사
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• 제14권3호
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• pp.9-21
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• 1981

The rationalization for Tunnel Drifting is based on the high productivity which is achievable due to Continuous work with a Jumbo Drill, resulting in a much higher efficiency them the Conventional method of blasting, mucking and supporting services. Large projects of over 4,000m Tunnel Drifting are condidated to justify the use of a Jumbo Drill with a combination of superior explosives, machinery and techniques. During a Tunnel Drifting test, Gulita, Nabit and slurry made by Nitro Nobel were employed with following results. 1, Conditions: a. Granite Rock with Two free face b. Burden (W), 2m c. Diameter of hole, 42mm d. Depth of hole 3.5m e. Hole pitch 0.6m f. Charged Explosive per hole Gelatin Dynamite 4 pieces (112.5${\times}$4ea)+Guuita 5 pieces(110g${\times}$5ea) g. Simal-taneous Detonation h. After the blasting resultant rock size was Less 40% of the 0.3m Lumps. 2. Calculation results W=q/Wn=100cm‥‥‥Burden in simultaneous blasting 0.865kg(7.7ea)/hole ‥‥‥Amount of charge but hole pitch is 1.5W-2W The estimated cost of using a Jumbo Drill for the Construction of a 3,000,000 bbL sub-surface oil storage would be as follows: This calculation is based on the Jumbo Drill advancing 3.6m per blasting cycle. Unit cost/bbL Excavation $3.13 The attached sheet shows ideal Drilling pattern with Burn Cut & Smooth blasting method. In conclusion, it is my opinion that this method will assure safety and save cost and improve our technical know-how.

• 한국작물학회지
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• 제40권4호
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• pp.481-486
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• 1995

염분농도가 상이한 1/2 Hoagland 수용액에 보리 유식물을 생육시켰을 때 수경액의 염분농도가 높아짐에 따른 몇가지 변화의 양상을 관찰한 결과를 요약하면 다음과 같다. 1. 지상부나 지하부의 생육량은 수경액에 25mM정도 NaCl이 함유된 때에 오히려 많았으나, NaCl 농도가 50mM 이상일 때에는 현저하게 감소하기 시작했다. 2. 식물체내의 수분함량은 수경액의 NaCl농도가 높아질수록 낮아져 염생식물과는 달리 식물체내에 있는 NaCl이 삼투압 조절물질로 작용하지는 않았다. 3. 수경액의 NaCl의 농도가 높아짐에 따라 초엽에 있어서 단위 면적당($cm^2$) 기공의 수는 많았으나(무처리;3,683, 100mM NaCl처리;5,153) 길이가 짧아져 약간씩 감소하였다. 4. 뿌리의 생장점은 수경액의 NaCl 농도가 75mM 이상인 경우에 핵분열이 심하게 저해되었다. 5. 수경액의 ,NaCl 농도가 75mM 이하의 경우 엽록체는 NaCl에 의해 stress를 받지 않아 형태적인 면에서 변화가 없었으나 근단 생장점의 Mitochondria가 파괴되는 현상을 볼 수 있었고 NaCl 75mM구에서 불규칙한 고형물질이 세포벽쪽에 밀집한 것을 관찰할 수 있었다.

• Journal of Chest Surgery
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• 제10권2호
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• pp.250-267
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• 1977

Open heart surgery has been performed on 20 patients, using hemodilution principle under the moderate hypothermia from Dec. 1975 through Aug. 1977 at the Department of Thoracic and Cardiovascular Surgery, Kyungpook National University School of Medicine. All these patients, body surface area ranged from 0.53 to 1.67$M^2$, were divided into two groups as a child group [below 15 yrs] and a adult group[above 15 yrs]. The oxygenator were primed with fresh ACD blood, 5 per cent dextrose, Hartmann`s solution, 15 per cent mannitol, sodium bicarbonate, dexamethasone and antibiotics. The average flow rate was 2.0 L/$M^2$/min. in child group and 2.3L/$M^2$/min. in adult group. The degree of hemodilution in child and adult group was 30.7% and 29.3% respectively. The minimal value of rectal temperature was $30.84{\pm}0.7^{\circ}C.$, in child group and $30.0{\pm}1.5^{\circ}C.$, in adult group. We studied the changes of hemodynamic status, blood components, electrolyte, acid-base status. blood lactic acid and urine output during and after cardiopulmonary bypass.

• 한국인쇄학회지
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• 제28권1호
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• pp.43-50
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• 2010

The 200mesh screen was tensioned and fixed on a frame. When applied tension to 5N and 10N per unit area, a side length of opening of the screen was 163.223${\mu}m$ and 168.224${\mu}m$, respective. But side length not tensioned was 158.879${\mu}m$. We knew that a side length of opening of the screen rarely changes with tension applied to the screen. The appearances that a side length of opening of the screen expand little are due to a decreasing diameter of thread by means of tension. In a thickness measurement of screen, While the high density mesh screen that had a lot of knots that crossed a line of latitude and longitude per unit area appeared a higher numerical value, the low density mesh screen that had a few knots appeared a low numerical value.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2004년도 학술발표논문집
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• pp.295-300
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• 2004

We consider a G/M/1 queue with two-stage service policy. The server starts to serve with rate of ${\mu}1$ customers per unit time until the number of customers in the system reaches A. At this moment, the service rate is changed to that of ${\mu}2$ customers per unit time and this rate continues until the system is empty. We obtain the stationary distribution of the number of customers in the system.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.886-895
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• 1993

Experimental were conducted to obtain information on the effect of airflow rates and bed depths on the resistance of coffee cherries and coffee beans available locally (Coffea Liberica). The airflow used were in the range of 0.06 to 0.6 cu. m/s-sq.m. The moisture content of the coffee cherries ranged from 10 % to 50% (wet basis) and that of coffee beans ranged from 12% to 30% )wet basis). Two methods of filling were used i.e. loose fill and packed fill. Pressure drops across the material bed in a vertical column were measured at several depths using inclined manometer. The pressure drop increased directly with air flow rate as well as bed depths. The effects of air flowrates and moisture contents on the resistance in terms of pressure drip per unit bed depth were analysed. The pressure drop per unit depth across the material bed varied slightly due to different depth. The resistance to airflow decreased with the increase in moisture content for loose fill. However, the effect of moisture content is not apparent for packed fill.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 기술교육위원회 창립총회 및 학술대회 의료기기전시회
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• pp.76-81
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• 2001

This paper place the focus the development of treadmill for rat in order to verify the effectiveness of exercise therapy. Up to now, in many medical laboratories treadmill have had to be remodeled for experiments with animal. Thus, it is necessary to develop the treadmills for animals only including rats. The treadmill has a DC motor which can make 600 revolutions per minute(600 RPM) and tension of the belt of the treadmill can be adjusted to prevent shift of the belt to any side. Velocity can be selected from 10m to 30m per minute increasing by 1m. The motor is controled by pulse width modulation(PWM) control mode using a 8bit microprocessor. In the future, the roller and motor need to be combined for improvement of stability and decrease of noise.

• 오토저널
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• 제10권3호
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• pp.31-37
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• 1988

A phase different method to evaluate the instrument error of roundness measuring instrument and the form error of specimens for the calibration of the instrument is used. An instrument with a rotary table supported by an air bearing was calibrated by using the standard balls as a standard. The calibration was carried out repeatedly by setting the same ball in 12 phase angles(per 30.deg.) on the table and by recording their roundness errors with a magnification of 100,000 times. As a result of data analysis of all the observations, readout at each of 144 orientations(per 2.5.deg.) from recorded data file, the error of performance of the instrument and the specimens are separated. In the particular instrument used in the present experiment, the error of the instrument was determined with the accuracy of 0.0164 (.mu.m) and the form error of the specimens was determined with the accuracy of 0.0264,0.0172(.mu.m), respectively. If the instrument was calibrated by using the above specimens, then the accuracy of the measurement of roundness error can be improved to about 0.017 (.mu.m).

• KSBB Journal
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• 제8권1호
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• pp.42-48
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• 1993

Continuous degradation of formaldehyde by using a rotating disc contactor was investigated in this study. Peudomonas putida H-5K was selected as a mutant using N-methyl N'-nitro N-nitrosoguandine (250$\mu\textrm{g}$/$m\ell$), which showed 1.5 times higher ability of formaldehyde degradation than that of the parent strain. Enzyme activity for formaldehyde degradation released form Peudomonas putida H-5K showed the highest level of 6.2mo1/min/mg protein in the 2% glucose mineral medium containing 0.02% formaldehyde. Degradation of formaldehyde from the first stage in rotating disc contactor was 95% and 5% from the 4th stage when the reactor was fed with 0.02% or 0.04% formaldehyde solution at a rate of 20$m\ell$ per hour. Continuous degradation of formaldehyde using rotating disc contactor was above 95%o in the medium containing 0.04% formalchyde, at the medium feed ratc of 20$m\ell$ per hour.

• 식물조직배양학회지
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• 제21권4호
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• pp.201-206
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• 1994

Glycine, valine, alanine과 histidine의 수송은 모든 실험된 중성 아미노산에 의해 경쟁적인 방해를 당하였다.그리고 reciprocal 연구 결과로 이들 중성 아미노산들은 서로 carrier reciprocal의 활성부위를 점유하기위해 경쟁하므로 같은 운반자를 소유한다. Histidine은 전하를 띄우지 않은 상태로 중성 아미노산 운반자를 통해서 능동수송된다. 중성 운반자의 $K_m$ 값은 아미노산이 운반자에 대한 친화성에 따라서 3가지로 분류하였다. 0.1 mM 보다 작은 값, 0.1 mM에서 0.5 mM 사이에 있는 값고 0.5 mM 보다 큰 값이다. $V_{max}\;는\;3.12mol{\cdot}h^{-1}{\cdot}g{\;}fresh{\;}weight^{-1}\;과\;15.1\;{\mu}mole{\cdot}h^{-1}{\cdot}g{\;}fresh{\;}weight^{-1}$ 사이에 있다. 중성 아미노산은 아미노산 한개당 수소이온 한개가 동반수송되고, $K^{+}$ 한개가 전하보상을 위해서 배출된다. Histidine 분자도 1 분자당 1개의 수소이온과 동반수송되나 전하를 띄운 histidine 분자로부터 수소이온 한개가 배지로 떨어져 나오므로 동반수송된 수소이온의 움직임을 일시적으로 측정 할 수 없다.